Subnanomolar determination of dopamine by electrochemical sensor based on AuNPs- MWCNTs and mannan-Os (VI) adducts
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Date
2015
Authors
Beden, Najat
Hamidi, Hassan
Palecek, Emil
Trefulka, Mojmír
Gorton, Lo
Journal Title
Journal ISSN
Volume Title
Publisher
iMedPub Journals
Published Version
Abstract
Electroactive adducts, comprising 3α,6α–mannan attached to the six-valent osmium complex with N,N,N´,N?-tetramethylenediamine (simply denoted, Man- Os (VI) tmen) was immobilized on the surface of graphite electrodes via a simple adsorption route and then covered with poly(sodium-4 styrene sulfonate) (PSS). Cyclic voltammograms of modified electrodes GE/Man-Os (VI) tmen showed a clear and well-resolved anodic peak for 1 mM of dopamine DA, ascorbate AA, and urate UA at the potential range of -50 to +350 mV vs. Ag|AgCl|(KClsat.) the sensor GE/Man-Os (VI) tmen/PSS was successfully used for sensitive and selective determination of DA in the presence of an excess concentration of AA and UA, 5 mM and 0.5 mM respectively, using differential pulse voltammetry. Under optimized conditions, the peak current densities were linear from 0.1 nM to 20 μM of DA with a sensitivity of 358 μA μΜ-1 and a detection limit LOD (3SD/slope) of 2.8 nM. Further modifying of the sensor using multiwall carbon nanotubes decorated with gold nanoparticles (AuNPs-MWCNTs) led to substantial improvement in its analytical characteristics. The linear response of the electrode modified GE/ AuNPs-MWCNT/Man-Os (VI) tmen to DA was spanned from 1 pM to 40 μM with a high sensitivity of 624.49 μA μΜ-1 and a LOD (3SD/slope) of 0.17 pM.
Description
Keywords
Au nanoparticles , Multiwall carbon nanotubes , Man-Os (VI) tmen polymer , Dopamine , Poly(Sodium 4-styrene sulfonate)
Citation
Beden, N., Hamidi, H., Palecek, E., Trefulka, M. and Gorton, L. (2015) 'Subnanomolar determination of dopamine by electrochemical sensor based on AuNPs- MWCNTs and mannan-Os (VI) adducts', Insights in Analytical Electrochemistry, 2(1), 1 (8pp). doi: 10.21767/2470-9867.100009